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The new round of power system reform has strengthened the supervision of transmission and distribution links, and changed the profit model of power grid enterprises by verifying the transmission and distribution price. In this context, the research on the regulatory risk faced by power grid enterprises under the electricity price regulatory policy can provide tools and decision support for power grid enterprises to accurately grasp the regulatory risk and reduce the risk loss. Firstly, combined with the transmission and distribution price supervision process faced by power grid enterprises, the possible risks faced by power grid enterprises in price supervision are analyzed. Secondly, the quantitative measurement model of electricity price regulation of power grid enterprises is constructed by using system dynamics, and the effectiveness of the model is verified. Finally, the future regulatory period is simulated and the results are analyzed, and policy recommendations are put forward.

The Al (021)/Al2CuMg (001) interface models based on experimental orientation relationship are constructed, the structure, work of adhesion, tensile strength, stacking fault energy (GSFE), doping modification, and electronic structure are investigated by first‐principles calculations. The CuMg‐terminated interface evolves into Al2‐terminated interface, which is consistent with experimental observations. Due to stronger bond strength, the M1‐type interface has higher work of adhesion (2.023 J m−2) and tensile strength (6.78 GPa) than these of M2‐type interface. Meanwhile, Ag doping can enhance the tensile strength of M2‐type interface to 6.63 GPa. By calculating the 2 d plot of GSFE, it is found that most slip directions for all interfaces are 12[110], [010], and [100] directions in Al2CuMg, respectively. Doping Ag atom improves the antislip ability of the M2‐type interface and further influences the tensile and slip properties of the Al/Al2CuMg interface. The charge density difference, electron localization function, and partial density of states demonstrate that the metallic and covalent bonds are mainly formed by Al‐2p orbitals at the interface, so the charge distribution of atoms in the vicinity of the interface is affected by the extranuclear electron of doping Ag atom. [ABSTRACT FROM AUTHOR]

The S phase (Al2CuMg) is an important strengthening phase for the Al–Zn–Cu–Mg alloys, which are widely used in the aerospace and transportation industries. First-principles calculations based on the density functional theory were used to investigate the effects of doping V, Nb, Cd, Ag, Ge and Sb elements on the S phase. The results demonstrate that Ag atom can spontaneously dope into the S phase. Ge and Sb doping can improve the toughness and plasticity of the S phase. And doping Ge, V or Nb can reduce the anisotropy of the Al2CuMg phase. The hardness of the Nb, V, Cd and Ag doped structures become larger than that of the pristine structure. The results of orbital hybridization in the partial density of states (PDOS) and the distribution in electron density difference (EDD) confirmed that the effect of doping elements and Al atoms has the greatest impact on the performance of the system, and the strength of the covalent bond of the system affects the main aspects of brittleness. This study provides a better theoretical understanding of the doped S phase, providing guidance for improved composition design and performance optimization of Al–Zn–Cu–Mg alloys. [ABSTRACT FROM AUTHOR]

Strengthening phase and element doping are two important methods to improve the mechanical properties of Al-Cu alloys. In this work, first-principles calculations based on the density functional theory were used to investigate the influence of doping elements (V, Co, Ca, Sr, Ga, As) on mechanical properties of θ phase (Al2Cu) in Al-Cu alloy. The results showed the additions of As and Ga can increase the strength of θ compound with decrement on ductility. But V and Co doping exhibited the opposite effect that they can enhance ductility and reduce some amounts of strength. And the strengths of Ca and Sr doped structures were increased in a few quantities. By analyzing on electronic structure, it is implied that there exists an apparent relation between orbital hybridization and the charge transfer of mechanical properties. This work provides a theoretical basis for understanding the doping mechanism in Al2Cu and a possible way to improve the performances of Al-Cu alloy. [ABSTRACT FROM AUTHOR]